We've got two numbers: 9852 and 3911. Let's find their sum.

Step 1: We'll start by adding the digits 2 & 1 in column 1 and get 3.

Step 2: We'll start by adding the digits 5 & 1 in column 2 and get 6.

Step 3: We'll start by adding the digits 8 & 9 in column 3 and get 17.
We'll write down the last digit 7 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 9 & 3 in column 4 and get 13.
We'll write down the last digit 3 and carry the 1 to the next column.

So, 9852 + 3911 = 13763.

